Thermoforming is a manufacturing process in which an object, such as a polymeric sheet or film, is heated until pliable, formed into a shape with a mold, and then cooled. Twin sheet thermoforming is a related process in which two objects are heated, formed by respective molds, bonded together while still hot, and then cooled to form, typically, a hollow article. With these processes, articles can be formed in a wide variety of shapes, and the articles can be produced efficiently using a variety of materials.
In the case of twin sheet thermoforming, the sheets are often loaded independently into the thermoforming oven, which can disadvantageously increase manufacturing time. Also, in some cases, the sheets are each connected to opposite sides of a spacer, and the assembly is loaded into the oven. In this latter case, attaching the sheets to the spacer can take a significant amount of time, and/or the formed part typically needs to be cut from the spacer, each of which reduces manufacturing efficiency. Moreover, in some cases, a frame, insert, or other object is sometimes introduced between the molds to properly form the article, and positioning these parts between the molds can be additionally time consuming and can negatively impact manufacturing efficiency.